Delta says it is now the only US-based airline to offer all in-flight entertainment free.

"The only thing better than operating the world's largest in-flight entertainment-equipped fleet is providing it free to all our guests," Delta Air Lines CMO Tim Mapes said in a statement. "Our commitment is to provide Delta customers with the industry’s best on-board services – period."

Delta Studios offers more than 300 movies, 750 TV shows, and 2,400 songs along with 18 channels of satellite TV.

As they have increased in profitability, US airlines have taken steps to reintroduce many of the creature comforts that were abandoned during the Great Recession. United and American have restored free snack service to coach passengers.

Free in-flight entertainment is just the next step. Both American and United offer free video streaming aboard their flights, but the availability of such services is not as widespread as in Delta's fleet.